A record number of people took the pledge to become Australian citizens at Australia Day ceremonies over the weekend, as the nation's foreign-born population continues to rise.

Almost 18,000 people became Australian citizens on Sunday, which has contributed to making more than a quarter of the country's population foreign-born.

The latest figures from the Australian Bureau of Statistics show people born in the United Kingdom continue to be the largest group of residents born overseas, accounting for 5.3 per cent of the population, followed by 2.6 per cent born in New Zealand, 1.8 per cent born in China and 1.6 per cent born in India.

Monash University's population researcher, Dr Bob Birrell, says Australia is an attractive destination for migrants because of its affluence and substantial job opportunities.

"That along with the opening up of our migration program by successive governments has led to a record high influx of both permanent and temporary migrants in recent years," he said.

As Australia's total population approaches 23.5 million, demographer Bernard Salt says the country's population is growing at close to record rates.

"At the current time, it's largely driven by overseas migration, which is tracking around 230,000 people per year," Mr Salt said.

Dr Birrell says Australia's population growth is exceeding those of many other countries around the world.

"We're growing at about 1.8 per cent a year, which is much faster than the other western countries and indeed most Asian countries," he said.

'Better opportunities'

People born in Nepal, India and Pakistan are among the fastest growing groups of migrants in Australia.

Electrical engineer and musician, Ranjan Vaidya, grew up in the Nepalese capital of Kathmandu and moved to Australia 15 years ago.

"I came to Australia mainly looking for better opportunities and also I heard about Australia as a fair go country, with hard working people," he said.

Mr Vaidya says most people from Nepal come for jobs, education and to get away from years of political instability.

"You have got a lot of things right here," he said.

"The political system is right, your economic system is right, all the prosperity, everything is right."

The main settlement point for those born overseas are the major cities of Melbourne, Sydney and Perth, as well as south-east Queensland.

"That's where the jobs are," Dr Birrell said.

"It's also where the major migrant communities are located and Asian migrants in particular prefer to settle where there are established communities of their own ethnic and religious backgrounds," he said.

According to the Organisation of Economic Cooperation and Development, about 73 per cent of people aged between 15 and 64 have a paid job in Australia and the average disposable income is nearly $US29,000 a year.

Life expectancy at birth is almost 82 years and the OECD says there's a strong sense of community.

Mr Salt says people can also find their own community within Australia.

"Australia has a place, I think, for everyone," he said.

"If you want to do the outback thing you can, if you want city sophistication you can, if you want to raise a family in middle suburban you can do that as well."

Room for more

Geographically, Australia is very diverse with vast coastlines, beaches, tropical rainforests and snowfields in between major cities and country towns, while nearly 20 per cent of the land mass is classifed as desert.

As the planet's 6th largest country, Mr Salt says there's room for more people.

He believes Australia can grow to over 30 million over the next 50 years.

"I think we have a moral obligation if you like, to accept migrants from overloaded parts of the rest of the world," Mr Salt said.

"There's also an economic argument that as the baby boomers move beyond the working age into retirement we need more workers or tax payers."

But Dr Birrell says a growing population is not without its challenges.

"Worsening congestion, inability to keep up with infrastructure, education, health and other areas are where the pressure points are at the moment," he said.

In addition, he says finding a job is becoming more difficult than it was a few years ago and the cost of living is on the rise.

It's those challenges the nation's governments will have to carefully consider when planning for more people.